DR BEKAII-SAAB: So this is a high-risk patient based on the size and the mitotic rate. And, of course, if you want to follow the spirit of the study that was discussed, then 3 years is optimal.
I think more practical question is: Should we continue beyond 3 years? And that’s really the question.
DR LOVE: So Alan, how would you estimate this patient’s untreated risk of recurrence? There are a lot of nomograms out there. I’m kind of curious, sort of eyeball what you think this patient’s original risk of recurrence was.
DR VENOOK: That’s a good question. It’s a jejunum mass, 6 centimeters, and, if really 7 mitoses per high power field, that’s a very high mitotic rate for GIST. I would put this patient’s risk of recurrence extremely high. I would guess 70, 80%. Just throwing it out there. Somebody might throw another number out. But that’s a very high risk of recurrence.
DR LOVE: So I’m just kind of curious, what would be your bar in terms of risk? Rich, you see a patient who’s had a GIST taken out. You put the patient’s numbers into the nomogram. Is there a ballpark number where you are going to treat?
DR GOLDBERG: I think the 50% level is still a good standard. What do you do with the 40 to 50% group? And I think you can ask the patient to participate in that conversation.
DR LOVE: So, Bert, again, agree, disagree or in between about the 50% mark?
DR O'NEIL: I’d probably set the bar a little lower, I guess, in terms of threshold. If you look at the ACOSOG study, which is what we consider a standard of care sort of study, and take the low end of the patients that were eligible for that study, they probably have a risk more in the 20% range. So I think if you’re following the eligibility for that study you are going to put patients with somewhat lower-risk disease on imatinib at least for a year. And I think somewhere in that 25% range is where I’d put my threshold for giving a patient a year of imatinib and, again, if they have higher-risk disease, then the 3 years.
DR LOVE: So Emily, how do you like these two? Do you want to choose, or in between?
DR BERGSLAND: I think they are kind of different groups. I think the people with a greater than 50% chance of recurrence, sort of a high-risk group, I mean that’s the group where you’re going to probably offer 3 years of therapy. And there’s even questions about whether that’s sufficient or optimal. But again, I think, as Bert pointed out, you have data from a study that included tumors down to 3 centimeters but didn’t include mitotic rate in the algorithm. And so again, I think it just leaves questions, that you have a positive study in tumors as small as 3 centimeters. And I think I would bring the patient into the discussion in terms of whether they want at least to have a year of therapy. And I think for these smaller tumors that might be the reasonable compromise.